I just got back from SD yesterday after spending New Years there. Great place to hang out, lot's to do.
Check out the downtown area. Gas Lamp is a great place to party and great restaurants.
Little Italy rocks.
Zagarella has some of the best Italian food around.
The Fish Market next to the Midway has a cool outdoor patio to hang out and slam appetizers and beer all night.
The Holiday Inn across the street from the Star of India has great govt/state emp discounts.
If it's a clear day, head out to Point Loma and check out the views and tide pools.
Pacific Beach has a cool place to walk around and shop
Just one block south of Little Italy on Kettner there's tons of cool antigue shops with some neat garage art stuff.
Take the ferry over to Coronado Isle and walk across to the Del. The homes along the walk are amazing for there price. Also, killer burgers at the Del.
Rent a GoCar